Metallurgical furnace.



U. WEDGE.

METALLURGIGAL FURNAGE.

APPLICATION FILED JULY 16,1913. A

Patented A131228, 1914.

noaana STATES I.

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' UTLEYWEDGE, or anniaonn, PENNSYLVANIA,

:umanitariUnteren Lf FURNAGE.

f Specification of Letters Patent,v v

Application led July l16', 1913, Serial No. 779,261. "t

\ L To all' wimml t may concern Improvements in Metallurgical Furnaces,-

of which the following is a specification.

`Theobj ect of my invention is to construct a furnace, particularly one ofthe circular hearth type, in such manner as to provide for the convenient conduct thereinr of processes that cannot be so conducted in furnaces of thistype as ordinarily built.v 1

This object I attain in the mannerv hereinafter Set forth, reference being had to the accompanying drawing, in Which- Figure 1 represents in vertical section a furnace of the circular hearth type with superposed hearths constructed in accordancewith my invention, and Fig.'2 a fur-V nace-of the rotary horizontal type, embodying my invention.

he furnace shown in `vFig. 1 may have any desired number of hearths, that shown in the drawing having seven hearths, numbered consecutively from top to bottom,

"these hearths vbeing supported upon the outer wallS and having central openings ,for the reception 'of the central rotating shaft 9 which is provided with projecting rabble arms l0 intended to carry appropriate rabbles for stirring and feeding the material deposited upon the hearths. In the drawing, the rabbles are, for convenience, shown upon the arm which cooperates with the hearth 2 only. Each of the hearthsdis- 'charges through a suitable opening or openp ings onto the hearthbeneath. rojecting upwardly from as many of the hearths as may be desired (from each of the hearths except the uppermost in the present instance) is an annular rib v11, which divides the hearth into inner and outer zones l2 and 13, respectively. The rabbles upon the arms 10 are so disposed as to feed the material over the 'zones 12 and 13 from the receiving.

to the discharge point. As shown in the drawings the direction of feed -over the zones 12 is radial, the discharge openings being locatednlternately at the outer and at the inner portions of said zones but the discharge openings of the `zonesl3 extend radially across the same and the material is fed by the rabbles in a circumferential course, the discharge opening of each. zone being slightly in advance of that of the zone beneath.

: If an extended travel of the material is is thus adapted for the performance of l -many operations which cannot be effectively performed in furnaces of the usual type, 'since 1n my improved furnace material of one character, can traverse the innenzonesv zones thereof, and thetwo operations can `thus be conducted simultaneously, for ;in-

Istance, carbonaceous fuel may be burned upon the outer zones and a compound of sulfur and iron, such'as a sulfid ore, may -be caused to traverse the inner zones of the hearths, the .combustion of the'fuel in the outer zones producing over' the inner zones a reducing atmosphere of suchl temperature as to vaporize the sulfur and .oxidize the :iron in the material on the upper hearths or reduce the metallic oXidto the metallic state on the lower hearths, or, where a reducing atmosphere is not necessary 'the' combustion 4of the fuel 011 the outer zones -may produce a heating gas for acting upon material on the inner zones, there being ingneither case any admixture of materi'al upon one zone with that upon the other zone. Where the furnace is one of the muifle type the necessary heating ofthe hearths" can be effected by products of combustion in the heating chamof the hearths and material of another' and' different character can traverse the jouter Patenten apr.. as, ima.

`required each zone 13 may have but a sinr i phere or other gaseous reagent can beproduced and maintained by means of gases evolved from suitable material deposited upon either the outer or the inner Zone of a hearth. i

'In practice it is preferable to deposit the ca'rbonaceous fuel or other gas producing material upon the outer zone because in case of leakage ofl air .through the walls of the furnace,- su'ch air will be compelled to mix` with the evolved gases before it can gain access to the material on the inner zone, and in y case a reducing atmosphere is to be maintained any air leaking into the furnace through the side walls would be deoxidized before reaching the material on the inner ZODB.

\ Steam may be introduced as by a suitably located pipe into those chambers of the fur-l purpose of supplying oxygen in such quantity and condition as to effect the desired oxidation of the metal without tending to .promote the oxidation of the sulfur.

My invention is not necessarily limited to a vertical furnace and in Fig. 2 I have illustrated the application of the same to a furnace of the rotary horizontal type, the barrel ,of such furnace being provided with internal spiral ribs 112.1 whereby it is separated into spiral hearths which are prevented from communicating with one another by means of said ribs, and either furnace may be constructed so as to provide more than two portions or zones on each hearth, if desired. A

In order to prevent, in a furnace of the type shown in Fig. 2, feed of material to any other zone of the furnace than that which is intended to receive the same it is advisable to provide'the feed spouts 14 with valves which may be opened when the proper. zone is beneath the spout and closed at other times. In 4Fig. 2 I have shown such valves in the form of slides 15 which canv be reciprocated by a cam 16 on the driving shaft 17 of the furnace, said cam acting through a rod 18 upon a bell crank lever 19 which reciprocates the rod 2O to which the slides 15 are connected. Each of the spiral hearths of the furnace may also have an independent outlet so as to prevent the mixing of the discharge from one hearth with that from the other.'

l/Vhcre it is desired to preveit oxidation of the material on the inner zones of the hearths the discharge outlet therefrom may be valved, as shown for instance at 21 and 22 in Fig. 1, so as to permit of the intermittent discharge of material without providing for any inflow of air.

I claim: I

1. A cylindrical furnace having a hearth with means dividing the same into a plurality of zones, and means for moving material over each of said zones.

2. A furnace having a series of superposed hearths provided with structures for separatingeach hearth into independent portions, and means for moving material over each portion of the hearth and from hearth to hearth of the series whereby such progressive movement can bc effected without adm-ixture of materials.

3. A cylindrical furnace having a series of superposed hearths provided with structures whereby each hearth is separated v ing structure Leggete into a plurality of zones, means for mechanically moving material over each of the zones and from hearth to hearth, the material on each Zone beingseparated from that on the adjoining zone.

11. A cylindrical furnace having a heart-h with a plurality of portions and a separating structure between them, means for feeding material independently to each .portion of the hearth, and means for moving the material over each portionof the hearth.

5. A cylindrical furnace having-a hearth with a plurality of portions and a separatbetween them, means for feeding material independently to each portion of the hearth, means for-moving the material over the different portions of the hearth,

and means for4 discharging the material from one portion of the hearth independently of the dischargefrom another portion of the same.

6. A circular furnace having a hearth provided with means for separating said hearthinto a plurality of zones, rabbles for moving the material over said zones, and a rotating structure carrying said rabbles.

7. A circular furnace having a hearth with means for separating the same into a plurality of zones, a central rotating shaft having one or morerabble arms thereon., and rabbles mountedin line respectively with the different zones of the hearth.

8. A circular furnace having a hearth with means for separating the, same into a plurality of zones, a central rotating shaft, one or more rabble arms thereon, rabbles c0- operating with one zone and-constructed to move the material over the same in one direction and rabbles cooperating with another zone and constructed to move the material over the same in a different direction.

9. A circular furnace having a hearth with means for separating the same into a plurality of zones, rabbles for each zone, and rotating mechanism for said rabbles, the rabbles coperatin structed to move tie material over the same in a circumferential course and those coperating with another zone being constructed to move the material over said Zone in a radial course.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

KATE A. BEADLE, HAMILTON D. TURNER.

with one Zone being con- 

